In the field of display technologies, to make a display panel thinner and lighter, it is increasingly popular to integrate display and touch sensing functions onto the same display panel, leading to the integration of a display unit and a touch unit in an In-Cell mode or an On-Cell mode, where the In-Cell mode refers to integration of the touch unit into the display panel, and the On-Cell mode refers to that the touch unit is independent of the display panel.
FIG. 1A is a schematic diagram showing a touch display panel in the related art. As shown in FIG. 1A, the touch display panel includes at least a driving circuit (not shown), a plurality of touch sensing electrodes 11, a plurality of scan lines 12 and a plurality of data lines 13. A plurality of sub-pixels 14 arranged in an array are defined by the plurality of scan lines 12 and the plurality of data lines 13 intersecting the scan lines 12, where each of the sub-pixels 14 is electrically connected with corresponding one of the data lines 13 via a control switch 15. Each of the touch sensing electrodes 11 may correspond to a plurality of the sub-pixels 14, and is electrically connected to a metal wiring 17 by a via hole 16. During a display phase of the touch display panel, a common voltage signal Vcom is applied to each of the touch sensing electrodes 11 through the corresponding metal wiring 17, and the driving circuit applies a scan signal to each of the scan lines 12 to scan a corresponding row of the sub-pixels 14 through the scan line 12 and hence turn on the control switches 15, and meanwhile applies data signals to the data lines 13 so that the data signals are transmitted to the sub-pixels 14 by the data lines 13, thereby driving the entire touch display panel to display an image. During a touch sensing phase of the touch display panel, the driver circuit stops provision of the scan signals and the data signals to the scan lines 12 and the data lines 13, i.e. the electrical connections of the scan lines 12 and the data lines 13 to the sub-pixels 14 are disconnected, and meanwhile a touch driving signal is provided to each of the touch sensing electrodes 11 via the metal wiring 17 to sense a position of a touch conducted by a user on the touch display panel, in order to achieve the touch sensing function.
FIG. 1B is a cross-sectional view of the touch display panel along a line A-A in FIG. 1A. As shown in FIG. 1B, the touch sensing electrode 11 is electrically connected with the metal wiring 17 by the via hole 16. The metal wiring 17 is configured to provide the touch sensing electrode 11 with the common voltage signal during the display phase, and provides the touch sensing electrode 11 with the touch driving signal during the touch sensing phase. Therefore, an additional process is required in manufacturing to form the metal wiring 17, and furthermore the via hole 16 is required for the electrical connection of the metal wiring 17 with the touch sensing electrode 11, resulting in complicated processes of manufacturing the touch display panel and an increased number of the processes, thereby significantly increasing the manufacturing cost. Additionally, the added metal wirings 17 further cause the uneven surface of the sub-pixel region, thereby affecting the display effect and increasing the risk of light leakage.